Recently, the size of wind turbines has been increased in order to, for example, boost the output power of wind turbine generators. The increase in the size of wind turbines, accordingly, has increased the hub height of wind turbines and at the same time has increased the weight of nacelles.
To support such a change, the size of cranes used for construction of wind turbines is also increased; however, it causes the problem of increased construction costs.
To solve this problem, a method has been proposed in which wind turbines are constructed with segmented wind turbine rotor blades, nacelles, and so on (see, for example, Non-patent Document 1).
The above method alleviates the increase in the size of cranes used for construction and therefore the increase in construction costs.
Non-patent Document 1:
“Four New Proposals”, 02: Segmented Nacelles and Segmented Blades, online, searched on Oct. 5, 2006, Internet <URL: http://www.fhi.co.jp/ecotechnology/wind/tech/index.html>